Around 800 jihadists have returned to Europe to launch attacks after being trained by extremists in Iraq and Syria, intelligence services have warned.

Counter-terrorism officers said the fanatics had been recruited by the Islamic State or Al Qaeda-linked groups and were waiting for the order to strike on the Continent.

Around half of the 700 Britons who have travelled to fight in the Middle East have also returned, with some believed to be planning attacks in the UK.

The warning comes after the Moroccan gunman who stormed a high-speed train from Amsterdam to Paris was said to be an 'Islamist returner' who had spent time in Syria.

Ayoub El Khazzani, 25, is believed to have been given instructions by a terrorist network to commit an atrocity, but was overpowered by six passengers, including three Americans and a British grandfather.

Some were being tracked, but others had dropped off the radar.

The source said: 'These people are not well trained, but they are poised and prepared to do anything. Once they have been indoctrinated, they receive the minimum training.'

A Spanish counter-terrorism source said Khazzani had lived in Spain for seven years until 2014.

He came to the attention of Spanish authorities for making hardline speeches defending jihad and attending a radical mosque in Algeciras.

Fairytales don’t tell children that dragons exist; children already know that dragons exist. Fairytales tell children that dragons can be killed. - G.K. Chesterton

Find the courage to proclaim Christ, … and the unchanging truths which have their foundation in Him. These are the truths that set us free! They are the truths which alone can guarantee respect for the inalienable dignity and rights of each man, woman and child in our world – including the most defenseless of all human beings, the unborn child in the mother’s womb. - Pope Benedict XVI

God does not choose the qualified. He qualifies the chosen - Madre Teresa de Calcutá

God gave us ten commandments, not ten thousand. Why? Why not a more complete list of specifics? Because he wanted freedom and variety. Why do you think he created so many persons? Why not just one? Because he loves different personalities. He wants his chorus to sing in harmony, but not in unison - Peter Kreeft

How monotonously alike all the great tyrants and conquerors have been; how gloriously different are the saints. - C.S Lewis

I would like to remind everyone, especially everyone engaged in boosting the world’s economic and social assets, that the primary capital to be safeguarded and valued is man, the human person in his or her integrity - Papa Bento XVI

If medieval people talked less about their own dignity, it is because they were more concerned about God´s dignity; if modern people talk more about it, it is because they are more concerned with themselves - Edward Feser

If you find a perfect parish, you go ahead and join her, it won't be perfect anymore - Matthew Kelly

In fact, a fine distinction could be a flat contradiction - G.K.Chesterton

It is true that I am of an older fashion; much that I love has been destroyed or sent into exile. G. K. Chesterton

Liberty cannot be established without morality, nor morality without faith - Alexis de Tocqueville

Mittite in Dexteram Navigii Rete, et Invenietis (João 21,6)

Multiculturalism is the doctrine which says that no culture can ever claim precedence over any other. So there can be no hierarchy of values, and no society can uphold its historic traditions and values against any challenge - Melaine Phillips

Napoleon himself announced to the Pope Pius VII that he was going to destroy the Church, to which Pius VII responded, “Oh my little man, you think you’re going to succeed in accomplishing what centuries of priests and bishops have tried and failed to do!”

Nowadays the devil has made such a mess of everything in the system of life on earth that the world will presently become uninhabitable for anybody but Saints. - Jacques Maritain

Of all tyrannies, a tyranny exercised for the good of its victims may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron’s cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end, for they do so with the approval of their own conscience - Clive.S. Lewis

One was the view that stars are personal beings, governing our lives (astrology); the other the general theory that men have one mind between them (marxism); a view obviously opposed to immortality; that is, to individuality - G.K Chesteron

The difficulty of explaining “why I am Catholic” is that there are 10,000 reasons all amounting to one reason: that Catholicism is true. - GK Chesterton

The divide in Western civilization isn't between rich and poor, red vs. blue, or the uneducated vs. the educated. It's God. God is the dividing line. You either believe God loves each of us and grants us inalienable rights or you believe that everything is negotiable including life - Matthew Archbold

The obedient are not held captive by Holy Mother Church; it is the disobedient who are held captive by the world! - Diane M. Korzeniewski

The true soldier fights not because he hates what is in front of him, but because he loves what is behind him - Chesterton

The two most destructive heresies — and the two most popular — are angelism, confusing man with an angel by denying his likeness to animals, and animalism, confusing man with an animal by denying his likeness to angels - Peter Kreeft

The whole of history is a struggle between two loves: love of oneself to contempt of God; love of God to contempt of self, in martyrdom. We are in this struggle.

There are only three kinds of people: those who seek God and have found Him — these are wise and happy; those who seek God and have not yet found Him — these are wise and unhappy; and those who live without either seeking God or finding Him — and these are both unwise and unhappy. - Blaise Pascal

There are two sorts of people who might be tempted to think of death as a friend: those who think the nature of the human person has nothing to do with the body, and those who think it has everything to do with the body; in short, Platonists and materialists - Edward Feser

To avoid therefore the evils of inconstancy and versatility, ten thousand times worse than those of obstinacy and the blindest prejudice, we have consecrated the state - Edmund Burke on French Revolution

To be or not to be – that is the question”, then the massive medieval doctor (St. Thomas) does most certainly reply in voice of thunder, “To be – that is the answer" - Chesterton